* the user can manually add additional update sites which will then also be checked for updates on startup
== Update site maintainer perspective ==
* <code>UpToDate</code> checks if the user wants to ignore updates, checks the internet connection, checks write access, etc..
* <code>UpToDate</code> also checks if any of the enabled update sites have different URLs on the available list of update sites (since Updater V1) and whether any update sites have a newer update timestamp than the one locally stored for that update site
* in case there are updates, <code>net.imagej.ui.swing.updater.ImageJUpdater</code>
* <code>ImageJUpdater</code> is the command creating the graphical user interfaces for dealing with updated files and update site URLs
== The official list of update sites ==